Amtrak officials say these specially designed trains will whisk travelers from downtown Boston to downtown New York in less than three hours, instead of almost four. Boston-to-Washington travelers will traverse the route in 5-1/2 hours instead of the present seven.

``The goal is to make the three-hour trip [from New York] to Boston ... an office on wheels, and thereby differentiate ourselves from what airliners provide.''

But several issues must be resolved for this $1 billion project. One problem is the curving Boston-to-New York railroad route that slows up high-speed rail service.

Meanwhile, concerns remain over the New Haven-to-Boston electrification project.

For the line between Boston and New York, Amtrak officials are looking seriously at a high-speed ``tilt train,'' which would travel at speeds up to 150 m.p.h.

The cars would automatically tilt to compensate for the pull of centrifugal force in curves. At least three of the company consortiums that are bidding for Amtrak's 26 new trains have some expertise in tilt-train technology.

The cost of the 26 new trains, to be built in the US, will run from $450 million to $500 million.

One of the bidding companies is ABB Traction Inc. of Sweden, which ran a demonstration tour of its X2000 high-speed tilt train through 85 US cities last year. ABB designed and built a tilt train that travels Sweden's 283-mile Stockholm-to-Gothenberg route in two hours, 59 minutes.

Conventional trains travel the route in 4-1/2 hours.

Amtrak agreed to let another bidder, Siemens Transportation Systems, run a demonstration of its German Inter City Express train (ICE) in the Northeast Corridor. The train was leased from German railways, which operates it between Hamburg, Munich, Frankfurt, and Berlin. Siemens also has expertise in designing tilt trains.

Mr. Carol of Amtrak says the tilt technology - which enables trains to travel 40 percent faster than usual through curves - will save only about five to 10 minutes in travel time. But he says ``every minute is crucial.''

High-speed trains

High-speed improvements on the Northeast train route have been in the planning stages since 1976.

The high-speed trains currently are limited to the New York-to-Washington stretch, which does not have the curves of the Boston-to-New York route. The 125-m.p.h. Metroliner trains that run out of New York and Washington span the route in only two hours, 55 minutes.

Improvements for Amtrak's Northeast rail corridor will involve upgrading the existing system to Metroliner-like service for the entire route - pending electrification of the New Haven-to-Boston rail line, according to Amtrak officials.

Currently, New York-to-Boston trains are delayed while electric locomotives are switched to diesel-powered ones in New Haven.

But the electrification project may be problematic. Connecticut residents are concerned about the noise of high-speed electrified trains passing through their areas. The Federal Railroad Administration will complete an environmental review of the electrification project in June.

Relieving clogged airports

Once the rail project is completed for operation in 1999, Amtrak's Northeast corridor will be the fastest high-speed system in the US. Unlike in other countries where high-speed passenger rail systems are built, the US system runs both freight and passenger service on the same tracks. They could leave Amtrak in the dust. France's TGV (train de grande vitesse) high-speed train zips along at approximately 190 miles per hour, as does the ICE train in Germany. Parts of Japan's high-speed rail system travel at 150 m.p.h. to 160 m.p.h.

Transportation experts say the new rail system could change the economic dynamics of the Northeast. For example, with high-speed rail, New London, Conn., will be less than 1-1/2 hours from Boston and less than two hours from New York City. And high-speed-rail advocates say the new improvements will reduce congestion at the nation's busiest airports.

``We just cannot build new airports in places like Boston and New York anymore, but we do have an ongoing transportation need that has to be met,'' says Joseph Vranich of the High Speed Rail/Maglev Association in Alexandria, Va.